RA, an autoimmune disease with a high incidence, can seriously threaten the health of the afflicted individual. Due to the limited knowledge concerning the etiology and pathogenesis of RA, controlling inflammation, alleviating the symptoms, and maintaining the functions of affected joints are the principal therapeutic aims when treating those diagnosed with RA. However, these treatments are far from the ultimate goal of preventing joint injury. With the development of novel molecular biology techniques in recent years, great progress has been made in our understanding of the pathogensis of RA, providing inroads into new therapeutic strategies.
In 1993, American scientists reported in for the first time their ability to successfully treat RA patients by using CCII (Trentham D E, Dynesius-Trentham R A, Orav E J, et al. Science, 1993, 261: 1727-1730), a finding which immediately attracted world-wide attention. Phase III clinical trials with CCII are underway in some developed countries, including America, Britain, and France. From a comprehensive analysis of the published literature we concluded that an oral tolerance approach, as a novel treatment, may increase our prospects for treating RA, by allowing investigation into both its root cause and symptoms (Trentham D E, Dynesius-Trentham R A, Orav E J, et al., Science, 1993, 261: 1727-1730).
To date, these clinical trials are only half-way toward completion and the pharmaceutical companies in developed countries are beginning to make CCII into an effective food additive to circumvent the laborious medication approval process. Though, internationally, natural CCII has been administered in studies of oral immunological tolerance for RA, its use in this manner also has severe drawbacks: 1) The quality of the obtained CCII differs from one company to another, as well as between batches from the same company, which makes it difficult to guarantee a consistent and continuous curative effect; 2) The continued extraction and preparation of CCII is time-consuming and requires a good deal of resources.
The inventor proposes a new approach, specifically a genetic engineering method for producing CCII, to solve the above-mentioned problems. We developed a technique to clone the CCOL2A1 gene, which can then be expressed efficiently in order to produce the recombinant CCII. The proposed invention relies heavily on the successful novel cloning of the polynucleotide sequence-CCOL2A1 cDNA encoding the full length CCII.